acknowledge vs revoke

acknowledge

verb
  • To own as genuine or valid; to assent to (a legal instrument) to give it validity; to avow or admit in legal form. 

  • To own or recognize in a particular quality, character or relationship; to admit the claims or authority of; to give recognition to. 

  • To be grateful of (e.g. a benefit or a favour) 

  • To admit the knowledge of; to recognize as a fact or truth; to declare one's belief in 

  • To report (the receipt of a message to its sender). 

revoke

verb
  • To cancel or invalidate by withdrawing or reversing. 

noun
  • The act of revoking in a game of cards. 

  • A violation ranked in seriousness somewhat below overt cheating, with the status of a more minor offense only because, when it happens, it is usually accidental. 

  • A renege; a violation of important rules regarding the play of tricks in trick-taking card games serious enough to render the round invalid. 

How often have the words acknowledge and revoke occurred in a corpus of books? (source: Google Ngram Viewer )